// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_WEBCRYPTO_ALGORITHMS_X25519_H_
#define COMPONENTS_WEBCRYPTO_ALGORITHMS_X25519_H_

#include "components/webcrypto/algorithm_implementation.h"

namespace webcrypto {

// This class implements X25519, a key agreement algorithm using the X25519
// function specified in RFC 8410. https://www.rfc-editor.org/rfc/rfc8410
class X25519Implementation : public AlgorithmImplementation {
 public:
  Status GenerateKey(const blink::WebCryptoAlgorithm& algorithm,
                     bool extractable,
                     blink::WebCryptoKeyUsageMask usages,
                     GenerateKeyResult* result) const override;

  Status ImportKey(blink::WebCryptoKeyFormat format,
                   base::span<const uint8_t> key_data,
                   const blink::WebCryptoAlgorithm& algorithm,
                   bool extractable,
                   blink::WebCryptoKeyUsageMask usages,
                   blink::WebCryptoKey* key) const override;

  Status ExportKey(blink::WebCryptoKeyFormat format,
                   const blink::WebCryptoKey& key,
                   std::vector<uint8_t>* buffer) const override;

  Status DeriveBits(const blink::WebCryptoAlgorithm& algorithm,
                    const blink::WebCryptoKey& base_key,
                    absl::optional<unsigned int> length_bits,
                    std::vector<uint8_t>* derived_bytes) const override;

  Status DeserializeKeyForClone(const blink::WebCryptoKeyAlgorithm& algorithm,
                                blink::WebCryptoKeyType type,
                                bool extractable,
                                blink::WebCryptoKeyUsageMask usages,
                                base::span<const uint8_t> key_data,
                                blink::WebCryptoKey* key) const override;

 private:
  Status ImportKeyRaw(base::span<const uint8_t> key_data,
                      const blink::WebCryptoAlgorithm& algorithm,
                      bool extractable,
                      blink::WebCryptoKeyUsageMask usages,
                      blink::WebCryptoKey* key) const;

  Status ImportKeyPkcs8(base::span<const uint8_t> key_data,
                        const blink::WebCryptoAlgorithm& algorithm,
                        bool extractable,
                        blink::WebCryptoKeyUsageMask usages,
                        blink::WebCryptoKey* key) const;

  Status ImportKeySpki(base::span<const uint8_t> key_data,
                       const blink::WebCryptoAlgorithm& algorithm,
                       bool extractable,
                       blink::WebCryptoKeyUsageMask usages,
                       blink::WebCryptoKey* key) const;

  Status ImportKeyJwk(base::span<const uint8_t> key_data,
                      const blink::WebCryptoAlgorithm& algorithm,
                      bool extractable,
                      blink::WebCryptoKeyUsageMask usages,
                      blink::WebCryptoKey* key) const;

  Status ExportKeyRaw(const blink::WebCryptoKey& key,
                      std::vector<uint8_t>* buffer) const;

  Status ExportKeyPkcs8(const blink::WebCryptoKey& key,
                        std::vector<uint8_t>* buffer) const;

  Status ExportKeySpki(const blink::WebCryptoKey& key,
                       std::vector<uint8_t>* buffer) const;

  Status ExportKeyJwk(const blink::WebCryptoKey& key,
                      std::vector<uint8_t>* buffer) const;

  const blink::WebCryptoKeyUsageMask all_public_key_usages_{};
  const blink::WebCryptoKeyUsageMask all_private_key_usages_{
      blink::kWebCryptoKeyUsageDeriveKey | blink::kWebCryptoKeyUsageDeriveBits};
};

}  // namespace webcrypto

#endif  // COMPONENTS_WEBCRYPTO_ALGORITHMS_X25519_H_